Small sanding jobs and sanding jobs calling for considerable detail work or access to small confined areas will usually require the direct hand application of sandpaper of one or more suitable grit sizes. The difficulty in hand-sanding is in applying firm pressure long enough to complete the job and in applying even pressure to obtain a desired smooth and even finish. A further difficulty is to obtain efficient use of the sandpaper by not wasting any substantial portion of its surface area.
Common sanding jobs calling for considerable detail work or access to small confined areas, or for the sanding of contoured surfaces, will often require that the surfaces be hand sanded. Therefore, hand-held sanding devices devised for this purpose consist essentially of a sanding block for holding conventional sandpaper wrapped over the block. By using a sanding block as a sandpaper holder, hand-applied sanding forces on the sandpaper can be increased and more evenly distributed. One such device is disclosed in U.S. Pat. No. 4,501,096 to Lukianoff, wherein a generally triangularly shaped sandpaper holding device provides three different sanding surfaces and corners for accommodating a variety of sanding conditions. The sandpaper wrapped around the faces of this device is held at its ends by means of an angled slot located in one of its faces.
The difficulty with the above-mentioned prior sanding devices is the necessity of installing or wrapping a separate piece of sandpaper around the device. This installation or wrapping process presents some inconvenience to the user, and the paper, if improperly installed, is susceptible to falling off. Also, the device requires the purchase of separate sheets of sandpaper which is a further inconvenience in terms of the amount of supplies needed.
Sanding blocks are presently available in a variety of forms in an attempt to meet the needs of those who must sand various surfaces. Perhaps the most common sandpaper support is a block of wood from which one may move through myriad supports and into complex electric sanders. In virtually all of these items, the general purpose of the sanding block is three fold.
First, it allows the user to apply greater pressure to the area being sanded. Secondly, it moves the user's hand away from the work surface, usually by providing a handle for the user to grasp, in order to reduce the likelihood of injuries. Thirdly, when a sanding block having a flat sanding paper supporting surface is used to sand a flat surface, the block reduces points of excessive pressure by more evenly distributing the user's force over the sandpaper supporting surface. However, when non-flat surfaces need to be sanded, difficulties often arise. The standard sanding block has a relatively large, flat sandpaper supporting surface which does not satisfactorily meet the needs of one who is sanding an irregular surface. The use of such a sanding block on an irregular surface will generally result in the user angling the block or using it in a way in which it was not intended in an attempt to conform the sanding surface to the work surface. Even with such attempts, the resultant effect is uneven sanding as generally no portion of the block will conform exactly to the area being sanded and excessive areas of pressure which will result in over sanding.
Excessive pressure points can also result in the quickened wearing of the sandpaper, such that the sanding block itself may become exposed, which, depending upon the fabrication of the sanding block, may damage the work surface. Similarly, as the user angles the sanding block in order to utilize a corner or edge of the sandpaper, a portion of the block not covered by the sandpaper may scratch the work surface.
In an attempt to provide sanding blocks which are usable on irregular surfaces, a wide variety of devices have been developed. For example, U.S. Pat. No. 3,557,496 to R.W. Martin discloses a metal strap to which a piece of sandpaper may be secured. The strap is then placed over a pipe or other circular type object so that a back and forth motion may be applied to sand the item. A circular piece of sandpaper is also secured over the handles which are particularly adapted for sanding the inner edges of the pipes. Other patents disclose devices such as special sandpaper holders for louver doors, U.S. Pat. No. 3,640,031 to Descant; sanding fittings, U.S. Pat. No. 3,722,150 to Pass; abrading corners and crevices as shown in U.S. Pat. No. 2,465,569 issued to Bates. While such devices may be suitable for their intended uses, they do not sufficiently meet the myriad surface irregularities often encountered when sanding a complex work piece.
Thus, an individual faced with the task of sanding a variety of irregular surfaces, must either attempt to use different types of sanding blocks, many of which still will not conform to the actual intended use, or in the alternative, those experienced in this area will use their hand in order to conform and support the sandpaper to the work piece. Attempting to enhance this latter approach are devices which either secure the sandpaper directly to the users hand or to a specialized glove.
It should be easily appreciated that these later approaches, while at times effective, are not reasonable alternatives when extreme precision or small detailed contours, such as in furniture finishing, are involved.
The present invention overcomes the forgoing difficulties of hand-held sanding devices by providing a hand-sized sanding device which eliminates the need for a separate sheet of sandpaper. A sanding device is particularly provided which has its own integral abrasive surfaces and which can be manufactured at a sufficiently low cost to be disposable. The invention further provides a self-contained sanding device that can be conveniently used off-the-shelf to hand sand a variety of standard, contoured or shaped surfaces, such as trim or molding surfaces, and for projecting into restricted exactly defined areas.